Recirculating filter

ABSTRACT

A self contained filter for a recirculating tank is used in a septic system. The self contained filter is a mattress-like filter made of woven material encapsulating aggregate material therein. The weave of the mattress-like woven material is smaller than the aggregate material. In another aspect, at least one mattress-like filter is placed within a tank.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention generally relates to a filter for arecirculating tank and, more particularly, to a self contained filterfor a recirculating tank used in a septic system.

[0003] 2. Background Description

[0004] Septic systems are widely used for a variety of applicationsranging from single family homes to industrial applications. Thesesystems also vary greatly in design; namely, aerobic and anaerobic typesystems. In either type of septic systems, the main objective is totreat wastewater in the most efficient manner in order to ensure thatthe water is properly filtered for distribution within a drain field orother distribution system.

[0005] In certain types of septic systems, a sand filter is used tofiltrate the wastewater prior to further treating or distribution of theeffluent. The sand filter is disposed within a recirculating tank andincludes several layers of varying sized aggregate. For simplicity ofdiscussion, the aggregate is manually disposed within the tank, with thelarger sized aggregate on the bottom of tank and the smaller or finersized aggregates progressively being layered toward the top of the tank.In some systems, one sized aggregate may be used to filter thewastewater; although, it is preferable to use at least a two or morelayered sand filter for more efficient filtering.

[0006] In operation, wastewater flows into the top of the tank. Thewastewater is then filtered through the several layers of the aggregateuntil the wastewater reaches the bottom of the tank. At the bottom ofthe tank, the filtered wastewater is then discharged to other portionsof the septic system. As is known in the art, the different sizedaggregates will filter different sized materials from the wastewater.

[0007] However, the use of sand filters pose several problems whichdecrease the efficiency of the filter and thus the cleaning of thewastewater. First, the top or finer layers of aggregate have a tendencyto migrate into the more course layers of aggregate. This migrationaffects the filtering properties of the system, and leads to the need tocompletely remove and replace all of the aggregate from the tank. Thisis a time consuming and costly procedure. Second, compaction of theaggregates also occurs within these systems. Compaction results inpuddling of the wastewater at the top of the tank due to lack of airspaces within the several layers of the aggregate. Much like migration,the aggregate within the tank must be replaced in order to correct thecompaction of the aggregate. Third, channeling also occurs in thesetypes of sand filters; that is, a channel or tunnel will be formedthrough all of the aggregate layers. This leads to poor filtering of thewastewater and the need, again, to replace all of the aggregate withinthe tank. The present invention is adapted to solving these and otherproblems.

SUMMARY OF THE INVENTION

[0008] An object of the present invention is to provide an efficientrecirculating sand filter tank used in a septic system.

[0009] Another object of the present invention is to prevent migrationof aggregate material within a recirculating sand filter tank.

[0010] A further object of the present invention is to preventcompaction of aggregate material within a recirculating and filter tank.

[0011] A still further object of the present invention is to preventchanneling of wastewater through aggregate material in a recirculatingsand filter tank.

[0012] Still another object of the present invention is provide a filterwhich is easy to install within a recirculating sand filter tank.

[0013] In order to provide the above advantages, the present inventionincludes a mattress-like woven material encapsulating aggregate materialtherein. The weave of the mattress-like woven material is smaller thanthe aggregate material. In another aspect of the present invention, atleast one mattress-like filter is placed within a tank.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The foregoing and other objects, aspects and advantages will bebetter understood from the following detailed description of a preferredembodiment of the invention with reference to the drawings, in which:

[0015]FIG. 1 shows a side view of a filter of the present invention;

[0016]FIG. 2 shows a cut-away view of the filter in a recirculatingtank;

[0017]FIG. 3 shows a cut-away view of several filters in a recirculatingtank;

[0018]FIG. 4 shows a top view of the filter and recirculating tank;

[0019]FIG. 5 shows a top view of an embodiment of the recirculating tankof the present invention;

[0020]FIG. 6 shows a left end view of an embodiment of the recirculatingtank of the present invention; and

[0021]FIG. 7 shows a side view of an embodiment of the recirculatingtank of the present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0022] The present invention is directed to a recirculating sand filterfor a septic system. The recirculating sand filter is a mattress-likefilter having aggregate or sand completely encapsulated therein. Themattress-like filter preferably contains synthetic aggregate material(e.g., particles) disposed therein, such as synthetic sand, but mayequally contain natural sand and other gravel products. For purposes ofthe present discussion, synthetic particles will be discussed herein;however, it should be understood by those of ordinary skill in the artthat the present invention is equally adaptable for use with naturalaggregate material.

[0023] In the embodiments of the present invention, the syntheticparticles will vary in size for each mattress-like filter. Themattress-like filter will be individually sealed once the syntheticparticles are placed therein. These individually sealed mattress-likefilters are then placed within a tank with the largest aggregate filledmattress-like filter preferably located near the bottom of the tank andthe finest aggregate filled mattress-like filters located towards thetop of the tank. The mattress-like filter of the subject inventionincludes several advantages;. namely, the filter prevents migration andcompaction of the particulate matter as well as prevents the channelingphenomenon. The present invention also is easy to transport and installwithin a septic system.

[0024] Referring now to the drawings, and more particularly to FIG. 1,there is shown a side view of a mattress filter of the presentinvention. The mattress filter is generally depicted as referencenumeral 2, and includes a woven fabric 4 or synthetic cloth. Syntheticaggregate material (e.g., particles) 6 is disposed within the wovencloth 4 and is preferably completed encapsulated therein. That is, thewoven cloth 4 is sealed using any conventional method after thesynthetic particles 6 are placed therein. In the preferred embodiments,only one sized particle 6 is placed within each individual mattressfilter 2. The weave of the woven cloth 4 is smaller than the syntheticparticles 6 placed therein so as to ensure that the synthetic particles6 remain within the mattress filter 2. This prevents migration of thesynthetic particles. A handle 8 may be placed on or integrally woven tosides of the mattress 2.

[0025] Still referring to FIG. 1, the synthetic cloth 4 is preferablypropylene or ethylene clothing. It should be understood, though, thatother materials, natural or synthetic, may also be used with the presentinvention. The synthetic particles 6 are preferably propylene,polychloride or other such material. The specific gravity of thesynthetic particles 6 should, in embodiments, be within the range ofapproximately 0.9+/−3%. This prevents the compaction of the syntheticparticles 6 due to the fact that at such specific gravity the syntheticparticles 6 will have a tendency to float. The sizes of the syntheticparticles 6 will depend on the specific application of use, but mayrange in size from 0.05 mm to 1½ inches diameter or more. The thicknessof the mattress 2 will also vary depending on the specific applicationof use, but is preferably approximately six inches thick.

[0026]FIG. 2 shows a cut-away view of the mattress filter 2 placedwithin a recirculating tank 10. An effluent piping system 12 is locatedat the top of the tank 10 and a perforated PVC return pipe 14 is locatedat the bottom of the tank 10 (below the mattress filter 2). Effluent 16flows into the tank 10 via the effluent piping system 12. The effluent16 then flows through the woven cloth 4 of the mattress filter 2 and isfiltered by the synthetic particles 6. The effluent, after beingfiltered, will then flow to the bottom of the tank 10 and into thereturn piping 14. In the embodiments, the mattress filter 2 willsubstantially fill the tank 10.

[0027]FIG. 3 shows a cut-away view of several mattress filters placedwithin the tank 10. As seen in this figure, the course syntheticparticles are placed in mattress filter 2 a at the bottom of the tank 10and progressively finer materials are placed in the mattress filters 2b-2 d, respectively. This provides for proper and most efficientfiltration of the effluent. It should be recognized that the presentinvention is not limited to the arrangement shown in FIG. 3, and thatother sized particles and combinations of mattress filters may also bedisposed within the tank 10.

[0028]FIG. 4 shows a top view of the mattress filter 2 and recirculatingtank 10. In this view, spray heads 12 a are shown extending from theeffluent piping system 12. The spray heads 12 a are used to distributethe effluent throughout the mattress filter 2 in an even distributionpattern. FIG. 5 shows a top view of an embodiment of the recirculatingtank 10. In this embodiment, the tank 10 includes troughs 10 aintegrally formed in the bottom and sides of the tank 10. The troughs 10a replace the piping 12 and 14 of the embodiment shown in FIGS. 2-4. Thetank 10 may be either precast concrete or a synthetic material such asplastic, PVC or other suitable material. An inlet pipe 10 b may extendfrom the interior to an exterior of the tank 10. A sheet 18 of plastic,PVC or other suitable material may be placed on either the bottom or thesides of the tank 10. If the sheet 18 is placed on the bottom of thetank 10, perforations are preferably placed within the sheet so thateffluent can flow from the mattress filter 2 to the integral troughs 10a.

[0029]FIG. 6 shows a left end view and FIG. 7 shows a side view of therecirculating tank of the embodiment of FIG. 5. In these views, a flange20 and ribs 22 are shown as part of the integral construction of thetank 10.

[0030] While the invention has been described in terms of preferredembodiments, those skilled in the art will recognize that the inventioncan be practiced with modification within the spirit and scope of theappended claims.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is as follows:
 1. A filter for use in arecirculating tank, comprising: aggregate material; and a mattress-likewoven material encapsulating the aggregate material, a weave of themattress-like woven material being smaller than the aggregate materialthereby preventing migration of the aggregate material.
 2. The filter ofclaim 1, wherein the aggregate material is synthetic particles.
 3. Thefilter of claim 2, wherein the synthetic particles are propylene orpolychloride.
 4. The filter of claim 2, wherein the synthetic particleshave a specific gravity of approximately 0.9+/−3%.
 5. The filter ofclaim 4, wherein the synthetic particles prevent compaction of thefilter.
 6. The filter of claim 1, wherein the aggregate material rangesin diameter from 0.05 nm to 1½ inches diameter.
 7. The filter of claim1, wherein the woven material is fabric or a synthetic material.
 8. Thefilter of claim 1, wherein the synthetic material is propylene orethylene clothing.
 9. The filter of claim 1, wherein only a single sizedaggregate is encapsulated in the woven cloth.
 10. A recirculating filtersystem adapted for use in a septic system, comprising: a tank; at leastone mattress-like filter placed within the tank, the mattress-likefilter having aggregate material sealed therein.
 11. The recirculatingfilter system of claim 10, wherein at the at least one mattress-likefilter is at least two mattress-like filters.
 12. The recirculatingfilter system of claim 11, wherein each of the mattress-like filtershave a different sized aggregate sealed therein.
 13. The recirculatingfilter system of claim 12, wherein a finer sized aggregate filledmattress-like filter of the at least two mattress-like filters is placedon top of a larger sized aggregate filled mattress-like filter of the atleast two mattress-like filters within the tank.
 14. The recirculatingfilter system of claim 10, wherein the aggregate material is syntheticparticles.
 15. The recirculating filter system of claim 14, wherein thesynthetic particles are propylene or polychloride.
 16. The recirculatingfilter system of claim 14, wherein the synthetic particles have aspecific gravity of approximately 0.9+/−3%.
 17. The recirculating filtersystem of claim 10, wherein the at least one mattress-like filter ismade from fabric or a synthetic material.
 18. The recirculating filtersystem of claim 17, wherein the synthetic material is propylene orethylene clothing.
 19. The recirculating filter system of claim 18,wherein a weave of the fabric or the synthetic material is small than adiameter of the aggregate material sealed therein thus preventingmigration thereof.
 20. The recirculating filter system of claim 10,wherein the tank includes troughs integrally formed in at least thebottom and sides thereof.
 21. The recirculating filter system of claim20, further comprising a sheet placed over the troughs of the side ofthe tank.
 22. The recirculating filter system 10, wherein the tank is aprecast concrete or a synthetic material.
 23. The recirculating filtersystem of claim 22, wherein the tank includes a flange and ribs disposedabout a periphery thereof.